Mabinee s compass



HALL COLBY, vOF ROCHESTER,4 NEW YORK.

, MARINERS COMPASS.

Specification of Letters Patent No. 5,096,v dated May 1, 1847.

To all whom t may concern:

Be it known that I, HALL ester, county of Monroe, and yStateof New York, have invented a new and Improved Mode of Preventing Mariners Compasses from being Eiected by Local and other Iniiuences and Attractions; and I do hereby declare that the following is a full and eX- act description.

The nature of my invention consists in providing duplicate or triplicate needlesv ar-y ranged on a line on the face of the card of the compass.

To enable others skilled in the art to make and use my invention I will proceed to describe its construction and operation.

I support the card by a brass spindle or needle and brace the same by a plate of brass or other metal on the under side of the cards and attach thereto the pivots upon COLBY, of Rochwhich the magnetic needles oscillate. Il

place two needles equally magnetized as lnumberedy l and 3. The concentrating or center needle being equally magnetized I make fast tothe cup as No. 2. By the polar iniiuence of theneedles over each other localk andA other influences and attractions are nearly overcome.

l/Vhat I claim as my invention and desire to secure by Letters Patent is. i

The arrangement in line, of duplicate or triplicate magnetic needles upon the card of the mariners compass by which local and` other influences and attractions are over c'omeinv the manner described.

` HALL COLBY.

lVitnesses T. C. DoNN, J. C. LEWIS.v 

